Switch for push key

ABSTRACT

A switch for a push key of a calculator or the like comprising, a switch case with built-in members and a cover. Hooks projecting downwardly from the cover engage with edges of an upper flange of the switch case and the extreme ends of said hooks fit into positioning holes bored in a supporting plate on the calculator. This enables the key-top to be mounted at a desired position.

[ 1 Feb. 27, 1973 United States Patent [191 Matsushima [s41 SWITCH FORPUSH KEY References Cited UNITED STATES PATENTS [75] Inventor: AkiraMatsushima, Chiba, Japan .200/168 C X 8/1969 Peroni et al.

3,609,268 Sanchez....................... [73] Assrgnee: Kabushlki KaishaHatton Tokelten, 3,462,719 335/206 Tokyo, Japan Primary ExaminerRoy N.Envall, Jr. Attorney-Robert E. Burns et al.

[22] Filed: Sept. 16, 1971 [21] Appl. No.: 181,080

ABSTRACT A switch for a push key of a calculator or the like comprising,a switch case with built-in members and a [30] Foreign ApplicationPriority Data Sept. 22, 1970 Japan cover. Hooks projecting downwardlyfrom the cover engage with edges of an upper flange of the switch caseand the extreme ends of said hooks fit into positioning holes bored in asupporting plate on the calculator. This enables the key-top to bemounted at a desired position.

6 Claims, 5 Drawing Figures SWITCH FOR PUSH KEY BACKGROUND OF THEINVENTION This invention relates to a switchfor a push key and moreparticularly to a switch for a push key of an electronic calculator andthe like.

DESCRIPTION OF THE PRIOR ART Conventionally in order to mount aswitchfor a push key to a frame of a calculator or the like a hole which meetswith the outside dimensions of the switch case is made in the frame, andthe switch case is inserted into this hole. A cover is puton the switchcase and is fineadjusted in such a manner that akey lever may bearranged in a regular or desired position and in a set order. Then thecover is screwed on.

In the construction described above, there is a disadvantage in that aclearance between the hole and the switch case occurs, and it is verydifficult. to for the switch case at its regular position, so that toscrew the switch case and the cover to the supporting plate afineadjustment is necessary- Thus it takes much time and labor to fixthe switch case and the cover.

SUMMARY OF THE INVENTION One object of the present invention is toprovide a switch fora push key which is provided with apositionregulating member and thus a keylever is arranged at the regularposition without fine-adjustment.

Another object of the present invention is to provide a switch for apush key which is easy to set on a switc supporting plate and simple inconstruction. 1

According to a feature of the present invention, there is provided animproved switch for a push key comprising a switch case with built-inswitch members and a cover for the switch case. The switch case isprovided with edges and the cover is provided with hooks engageable withthese edges. The hooks fix their extreme ends into positioning holesbored in a supporting plate.

BRIEF DESCRIPTION OF THE DRAWINGS These object, other objects and thecharacteristic features of the present invention will become evident andwill be more readily understood from the following description andclaims taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan view of a switch case according to the invention; Y

FIG. 2 is a plan view of a cover of the switch case of FIG. 1;

FIG. 3 is a sectional view taken along section line III-III in FIG. 1;

FIG. 4 is. an enlargedfragmentary sectional view along section line IVIVin FIG. 2; and

FIG. 5 is a fragmentary bottom view showing the positioning portion of asupporting plate in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,in the center of a switch case 1, is provided a cavity or space 2 inwhich a key level 3 is slidably accommodated. A permanent magnet 4 ismounted in a hole bored in the central portion of the-key lever 3. Amagnetically permeable plate 5 is fixed to the back side of thepermanent magnet 4. Lower end portions of the magentically permeableplate 5 are hooked or L-shaped and protrude through the lever 3, andanother lower end portion of the plate 5 is reversely booked and forms aspring book 6. The key lever is provided with two washers 7 made of.rubber axially spaced from each other. The lowermost end of the keylever 3 can protrude into a hole 8bored in the bottom of the case 1. Infront of the magnet 40f the case 1, there is provided a reed switch 9.An upper side reed wire 10 is bent and led to a printed circuit board,and another reed wire 11' is also connected to a certain point of theprinted circuit board by soldering or the like. A cushion materialelongated washer Bis provided in the hole in which the reed switch 9 isinserted.

At the top of the switch case 1, a circumferential flange I4 is formed.This flange is nearly square as shown in FIG. 1, and one pair ofopposing corners is cut off to form engageable edges and in the otherpair of opposing corners are bored mounting holes 16, 16. A cover 17 hasat the center thereof a hole 18 through which the top of the key lever 3slidably protrudesand a spring hook19 is provided opposed to the springhook 6. A coil spring 20 is connected at opposite ends between thespring hooks 6 and 19.

In the cover 17 mounting holes 21, 21 are bored at opposite cornerscorresponding to the mounting holes 16,. 16 of the switch case I. At theother pair of opposite comers there are provided downwardly extendingcatches or hooks 22, 22 engageable with the engageable edges 15, 15 ofthe case as shown. These hooks 22, 22, as shown in FIG. 4 and FIG. 5,project inwardly from square depending portions and the axial endsof'the hooks are formed as conically shaped or bevelled portions 23, 23.In a supporting plate 24 of a calculator is provided a hole or opening25 into which the case 1 is inserted. Positioning holes 26, 26 andmounting tapped holes are likewise provided. The positioning holes 26,26 are bored at selected positions and they receive the depending ordownwardly extending mounting portions 23, 23. The mounting holes arepreferably round-shaped into which the square or rectangular fittingportions 23, 23 are forced, as shown in FIG. 5.

In the operation the cover 17 is mounted on the switch case 1 in such amanner that the upper portion of the key lever 3 protrudes from the hole18, and the upper end of the coil spring 20 is mounted over the hook 19.When the cover 17 is pressed to the switch case 1, the bevelled tips ofthe hooks 22, 22 of the cover engage the top flange of the case and thehooks bend slightly outwardly and snap over the flange 14 to engage withthe edges l5, 15 of the switch case 1. The switch case 1, covered withthe cover 17 in the manner described above, is inserted into the hole 25of the supporting plate 24, and the mounting portions 23, 23 are forcedinto the positioning holes 26, 26. The hooks 22, 22 are square-shaped incross section and the positioning holes 26, 26 are round-shaped, so thatthe hooks are pressed into the positioning holes even if the holes are alittle tight for the hooks. Thus the key lever 3 is arranged in aregular position. Finally the switch case 1 and the cover 17 are fixedt0 the supporting plate 24 by screws 27, 27 threaded in the threadedmounting holes 21, 21 and 16, 16. Those skilled in the art willunderstand that the switch operates in known manner upon axial actuationof the push key. The spring 20 biases the push-key upwardly and when itis actuated by depressing it the magnet carried thereon closes the reedswitch elements and upon release of the key it is restored to its raisedposition and the switch opens.

What I claim and desire to secure by Letters Patent 1. For use in acalculator and the like, in combination, a push-key, a switch case,switch means in said case having contacts operable to a closed and openposition in response to actuation of said push-key, means on said switchkey for actuating said switch contacts, a cover on said case havingintegral thereon snapon hooks extending in a direction for engagingcatch surfaces on said case, a support member having mounting holes, andsaid hooks having portions extending past said cover surfaces when saidcover is mounted on said case for being received snugly in said mountingholes on said support member.

2. The combination according to claim 1, in which said hooks comprise, aportion mounted adjacent the periphery of said cover bendable outwardlyfrom said periphery for clearing said case and snapping back to engagesaid hooks on said surfaces.

3. The combination according to claim 1, in which said switch comprises,a reed switch, said means on said push-key for actuating said contactscomprising a per manent magnet.

4. The combination according to claim 3, in which said integral hookscomprise, a bendable plastic material.

5. A case for a push-key comprising, a body, a cover having an openingfor inserting a key therein into said body, said body having an innerspace for housing a push-key actuated switch, said cover having agreater transverse dimension than said body, said cover having integralhooks extending in a direction for engaging surfaces on said case body,said hooks having shanks integral with said cover and having bevelledsurfaces for engaging said body and being actuated outwardly away fromsaid body and snapping back to engage said body, said body having flangesurfaces for actuating said hooks outwardly when said bevelled surfacesare pressed against said flange surfaces and undersurfaces defining thefirst-mentioned surfaces engaged by said hooks.

6. A case for a push-key according to claim 5, in which said bevelledsurfaces extend downwardly of said hooks for being received in mountingopenings on a support member on which case is mounted.

a: a: a:

1. For use in a calculator and the like, in combination, a pushkey, aswitch case, switch means in said case having contacts operable to aclosed and open position in response to actuation of said push-key,means on said switch key for actuating said switch contacts, a cover onsaid case having integral thereon snap-on hooks extending in a directionfor engaging catch surfaces on said case, a support member havingmounting holes, and said hooks having portions extending past said cOversurfaces when said cover is mounted on said case for being receivedsnugly in said mounting holes on said support member.
 2. The combinationaccording to claim 1, in which said hooks comprise, a portion mountedadjacent the periphery of said cover bendable outwardly from saidperiphery for clearing said case and snapping back to engage said hookson said surfaces.
 3. The combination according to claim 1, in which saidswitch comprises, a reed switch, said means on said push-key foractuating said contacts comprising a permanent magnet.
 4. Thecombination according to claim 3, in which said integral hooks comprise,a bendable plastic material.
 5. A case for a push-key comprising, abody, a cover having an opening for inserting a key therein into saidbody, said body having an inner space for housing a push-key actuatedswitch, said cover having a greater transverse dimension than said body,said cover having integral hooks extending in a direction for engagingsurfaces on said case body, said hooks having shanks integral with saidcover and having bevelled surfaces for engaging said body and beingactuated outwardly away from said body and snapping back to engage saidbody, said body having flange surfaces for actuating said hooksoutwardly when said bevelled surfaces are pressed against said flangesurfaces and undersurfaces defining the first-mentioned surfaces engagedby said hooks.
 6. A case for a push-key according to claim 5, in whichsaid bevelled surfaces extend downwardly of said hooks for beingreceived in mounting openings on a support member on which case ismounted.